There are two issues that may cause your error.
1) Using VariPrint in Windows 7 OS, and haven't done setup of folder permission after installation. please go to http://www.haiyaatech.com/english/bbs/b_kantie.asp?tiezi=556 for reference.
2) You may not install Microsoft .net framework 2.0 or above in your computer. This is precondition of VariPrint operation. please check.